(a) Field of the Invention
The present invention relates to a three-layered solid golf ball structure.
(b) Description of the Prior Art
In playing golf, good golf equipment is as important as good golf skill. For solid three-layered golf balls, their quality is determined by three factors. The first is a preferred sense of striking, i.e., it permits the player to control the direction of the striking of the ball. The second is the rate of self-spinning of the ball, which, when all external conditions are matched, allows the ball to fly through a farther distance and to land on the ground without much bouncing. The third is the strength of the ball. The greater the strength of the ball, the longer its usable life. FIG. 1 shows a conventional solid three-layered golf ball 1. It essentially comprises a core 11, an intermediate layer 12, and an outer shell 13. The core 11 is made of an elastic material compounded mainly from a high elastic polymer and various high performance additives. The intermediate layer 12 is comprised of a multiplicity of rubber threads repeatedly wound on the circumference of the core 11. The outer shell 13 is made of an ionomer resin. Compared to a two-layered golf ball, the three-layered golf ball 1 as such has a preferred sense of striking to permit better ball controllability. However, as it has a high rate of self-spinning, although it can land on the ground in a preferred manner, the flying distance is not good. And besides, since the intermediate layer is comprised of rubber threads, the strength of the golf ball is low. Under a forceful striking, the rubber threads may disengage from the surface of the core 11. In other words, the intermediate layer 12 will become detached, and the durability of the golf ball is comparatively poor. Moreover, a strange sound will emit the instant the ball is hit. FIG. 2 shows another type of a three-layered golf ball 2. The golf ball 2 includes a core 21, an intermediate layer 22, and an outer shell 23. The core 21 is made of an elastic material compounded using a high elastic polymer as a major material and various high performance additives. The intermediate layer 22 is made of a thermoplastic elastomer material. The outer shell 23 is likewise made of an ionomer resin. In this three-layered golf ball 2, since the intermediate layer 22 is made of a thermoplastic elastomer, it has preferred strength, enhanced sense of striking, and farther flying distance, as compared with the golf ball 1 described above. However, the intermediate layer 22 does not have the softness of the rubber threads. Therefore, although the flying distance is better, the landing of the golf ball is not as good. Hence, improvements on the prior art are desirable.